Having some trouble adjusting to power pedals (going from VP to Favero)

So I’ve been riding my gravel bike on a CycleOps Mag+ Classic trainer. Was using Virtual Power and everything seemed to be going great. Recently bought a set of Favero DuoShi pedals so that I can train with power outdoors once the snow melts this Spring. Having trouble adjusting to the Favero pedals. Them seem really ‘finicky.’ My word only. And I’m using 3-sec power smoothing. Here’s what I mean.

Back when I was just using VP, hitting the power target during interval training (or any training) felt really easy. Just make sure you’ve got the gearing right, pedal fast enough and – BAM! – TR likely says you’re hitting the power target for that particular interval. And I understand why that is – there’s a correlation between wheel speed (based on the Mag+ power curve and how VP calculates output). And you even see that reflected in the results. Since I have 3 second smoothing turned on, it takes a few ticks for the VP calculation to catch up (see screen shot below).

But when I just did a VO2 max workout this evening, everything felt (to me) like it was going haywire. And I totally get that the Favero pedals are measuring actual force I’m applying to the pedals, but what’s happening during every interval is that I’m hammering hard to accelerate for the interval power target – and that’s reflected in the power spike – but then my power naturally drops off as I’m trying to bring it back down to the actual power target. And presumably the flywheel effect kicks in, etc.

So over the course of a 30 sec VO2 interval, the power target, let’s say is 225. I’ll be at 250 briefly at the beginning of the 30 sec interval as I try to quickly accelerate. And then as soon as I get my cadence up, my power drops to 215, or even 190 as my performance “stabilizes” for the remainder of the 30 sec interval.

And when I completed Taylor -2 just now, TR asked me what was up post workout (presumably because my TSS was only 54 out of 70). For better or worse, when I used VP, if I completed the workout, I generally always hit the TSS and IF.

Attaching a few screen shots of Taylor -2 which I just did with the new Favero and Grassy Ridge -2 which I just completed last week using VP.

Should I just be hammering all the time to hit the watt target? At some point I’m going to run out of gears, or can’t spin fast enough.

Or do I just not sweat it given that I’m using a classic trainer?



Hang in there, you’ll get better with practice!


VP is a different animal from actual power in the longer term once you get used to it working to actual power will be good for you. One thing when you got your new power meter, did you do a new FTP test with it?

1 Like

No. I did not do a new FTP test.

It would be advised then, VP can be massively different from actual power.


I agree, retest to get a new FTP. When i went from VP to smart trainer my “FTP” dropped over 30 watts. I would also use the earlier intervals to figure out what gear and cadences best suit the power you are trying to hit in each interval. Dont worry about instantly getting to the intervals power either. You can start ramping up a second or two before it starts then use the first few seconds of the interval to get your self up to the required power and stablize your cadence.


You’re probably already doing something like this, but just in case it helps, I tend to do it like this → about 3-5 seconds before the interval prepare for that surge by either speeding up my cadence to ~100-110rpm (for seated) or dropping it to prepare for standing. For seated, I just spin that higher cadence for a few seconds until the power goes past target and then slowly back off to my preferred cadence. For standing, I will shift up 3 cogs and then stand up with a few big pushes right when the surge begins, then shift back down before I sit and spin faster. Doing this, I get the spike at the beginning like you do, but I don’t end up way below target for the 2nd half of the interval like you did.

1 Like

It looks like it asked you why you struggled because you didn’t hit your targets on the last interval. Those 30 second intervals look more like hard start sweet spot efforts than vo2 max. As others have mentioned, retesting will help

Yes, you should be trying to hit the watt target. On a dummy trainer, sometimes that will feel like you are spinning faster than you want if you don’t have the right resistance.

If you are spinning too fast at these intervals and you can’t increase the resistance, you might need a different dummy trainer. I used to have the dummy + favero set up and could go 30-30s at a little over 300 watts without running our of gears. If I didn’t have the right resistance I had to have a cadence around 110 which feels extraordinarily fast when you are inside on the trainer.

I wouldn’t sweat needing a couple of seconds to settle in. Even with ERG mode things like changing cadence will cause the same effect. Most likely to a lesser degree, but it is still there.

1 Like

Thank you all. Some really good suggestions. I appreciate it.

Good idea. I’ll do that.

This, along with the need to re-test my FTP is perhaps the core of what’s going on. I’m already working at the top of my gearing range (it’s a gravel bike), and it just feels like I need more resistance working against me. I’ll need to check what resistance setting I’m at currently on the Mag+ and adjust it accordingly. At least “max” it out, etc.

Please correct me if I’m mistaken, but I’m assuming any lack of resistance concerns naturally go out the window when I train outside with power?

I depends where you ride, and what your target power is. It’s very hard to hold a higher power going downhill, for example. Ideally you want a long climb that’s consistent and not too steep.

1 Like

Ok. That makes sense.